KR100846983B1 - Apparatus and method for driving a plasma display panel - Google Patents

Abstract

The present invention relates to a method of driving a plasma display panel in which a configuration of a sustain discharge signal is changed to improve a low temperature generated at a high temperature when the plasma display panel is driven.

A plurality of scan electrodes, a plurality of sustain electrodes, a plurality of address electrodes formed in a direction crossing the scan electrodes and the sustain electrodes, and include a capacitor for power charging and charging, an inductor serving as a power transmission path, and a plurality of switches. A driving method of a plasma display panel including an energy recovery circuit includes: applying a first sustain discharge signal n times in succession to a rising time caused by resonance of a sustain discharge signal applied to the scan electrode or the sustain electrode; And continuously applying a specific second sustain discharge signal m times longer than the first sustain discharge signal.

Plasma display panel, ERC, energy recovery circuit, rise time.

Description

Driving apparatus and method for a plasma display panel {The Apparatus and Method of Driving for Plasma Display Panel}

1 is a structural diagram of a conventional AC type 3 electrode surface discharge type plasma display panel;

FIG. 2 is a timing diagram for describing a driving signal applied to the panel shown in FIG. 1;

3 is a block diagram showing a driving apparatus of a plasma display panel to which the present invention is applied;

4 is a view showing an energy recovery circuit to which the present invention is applied;

5 is a diagram illustrating an optical output according to a rising slope of a sustain discharge signal;

6 is a view showing a driving waveform to which the first and second sustain discharge signals are applied according to an embodiment of the present invention;

FIG. 7 is a graph showing experimental data on a lower reduction effect according to a mixing ratio of a first sustain discharge signal and a second sustain discharge signal; FIG.

FIG. 8 illustrates driving waveforms to which first and second sustain discharge signals are applied according to another embodiment of the present invention; FIG.

The present invention relates to a method of driving a plasma display panel, and more particularly, to a plasma display panel driving apparatus and method for changing the configuration of the sustain discharge signal in order to improve the low temperature generated at the high temperature when driving the plasma display panel. will be.

First, the conventional plasma display panel and a driving method thereof will be briefly described.

Fig. 1 shows the structure of a conventional AC type three electrode surface discharge type plasma display panel.

Referring to FIG. 1, between the first and second substrates 10 and 13 of the plasma display panel 1, the address electrode lines AR1, AG1,..., AGm, ABm, the dielectric layer 11, 15) Scanning electrodes Y1, ... Yn, sustain (common) electrodes (X1, ... Xn) and a magnesium monoxide (MgO) layer serving as a protective layer provided in pairs and parallel to the address electrode in parallel with each other; 12 is installed. In addition, barrier ribs 17 are formed to separate the address electrode lines, and fluorescent materials 16 are coated on the barrier ribs 17 so as to emit visible light of R, G, and B for each line.

In the driving method basically applied to such a plasma display panel, reset, address, and sustain steps are sequentially performed in the unit subfield. In the reset phase, the charge states of all display cells are uniform. In the addressing step, a predetermined wall voltage is generated in the selected display cells. In the sustaining step, a predetermined alternating voltage is applied to all the XY electrode line pairs, so that the display cells in which the wall voltage is formed in the addressing step cause sustain discharge. In the sustaining step, plasma is formed in the discharge space 14 of the selected display cells causing the sustain discharge, that is, the gas layer, and the fluorescent layer (16 in FIG. 1) is excited by the ultraviolet radiation to generate light.

FIG. 2 is a timing diagram illustrating a driving signal of the panel shown in FIG. 1. The address electrode A and the common electrode X in one subfield SF in the ADS (Address Display Separation) driving method of the AC PDP. And a drive signal applied to the scan electrode (Y).

Referring to FIG. 2, one subfield SF includes a reset period, an address period, and a sustain discharge period.

In the reset period, the reset signal is applied to the scan lines of all groups to force the write discharge, thereby initializing the wall charge states of all the cells. The reset period is carried out before entering the address period, which is carried out over the entire screen, making it possible to create a fairly even and evenly distributed wall charge arrangement. In the rising period of the reset period, the voltage of the Y electrode is gradually raised from the voltage of Vs to the voltage of Vset with the A electrode held at the reference voltage. As the voltage of the Y electrode increases, a weak discharge (hereinafter referred to as "weak discharge") occurs between the Y electrode and the X electrode and between the Y electrode and the A electrode, and a negative wall charge is formed on the Y electrode. Positive wall charges are formed on the X and A electrodes. When the voltage of the electrode gradually changes, a weak discharge occurs in the cell, and wall charge is formed so that the sum of the voltage applied from the outside and the wall voltage of the cell maintains the discharge start voltage state.

Subsequently, in the falling period of the reset period, the voltage of the Y electrode is decreased to the Vs voltage while the A electrode is maintained at the reference voltage, and then gradually decreased to the Vnf voltage. Then, while the voltage of the Y electrode decreases, a weak discharge occurs between the Y electrode and the X electrode, and between the Y electrode and the A electrode, so that the negative wall charges formed on the Y electrode and the positive wall charges formed on the X electrode and the A electrode Is erased. The cells initialized by the reset period have similar wall charge conditions in the cells.

The address period is performed after the reset period is performed. At this time, in the address period, the bias voltage Vb is applied to the common electrode X, and the display cell is selected by simultaneously turning on the scan electrode Y and the address electrode A at the cell position to be displayed. In the address period, a scan signal of size VscL is input to the scan electrode for the cell to be turned on.

After the address period is performed, the sustain signal Vs is alternately applied to the common electrode X and the scan electrode Y to perform the sustain discharge period. During the sustain discharge period, a low level voltage (0V) is applied to the address electrode (A). In the PDP, the luminance is adjusted by the number of sustain discharge signals. When the number of sustain discharge signals in one subfield is large, the luminance increases.

Such a plasma display panel has a characteristic that its discharge start voltage and discharge characteristics vary with temperature. According to Paschen's law, which describes the basic principle of plasma generation, the discharge start voltage (V) is the product of the pressure (P) of the gas and the distance (D) between the electrodes when discharging in the gas as shown in Equation 1. Proportional to

Therefore, when the temperature inside the panel rises, the pressure inside the panel rises, so that the discharge start voltage increases when the distance between the electrodes is constant. As the discharge start voltage increases, the address discharge may not occur well, which leads to a low discharge phenomenon in which sustain discharge does not occur or weakly occurs in the sustain period.

In order to solve the above problems, the plasma display panel is driven to solve the high temperature low temperature problem by grouping and applying the first and second sustain discharge signals having different rise times of the sustain discharge signals applied to the electrodes of the plasma display panel. It is an object to provide a method.

In order to achieve the above object, a plurality of scan electrodes, a plurality of sustain electrodes, a plurality of address electrodes formed in a direction crossing the scan electrode and the sustain electrode, and a power charging and discharging capacitor, A driving method of a plasma display panel comprising an inductor and an energy recovery circuit including a plurality of switches, the first sustain discharge signal specifying a rise time due to resonance of a sustain discharge signal applied to the scan electrode or the sustain electrode is continuous. N times, and applying a specific second sustain discharge signal m times in succession longer than the first sustain discharge signal.

In addition, the present invention includes a plurality of scan electrodes, a plurality of sustain electrodes, a plurality of address electrodes formed in a direction crossing the scan electrodes and the sustain electrodes, and include a capacitor for power charging and charging, an inductor serving as a power transmission path, and a plurality of scan electrodes. A method of driving a plasma display panel including an energy recovery circuit including a switch, wherein a sustain discharge signal is applied to only one of the scan electrode and the sustain electrode, the first sustain time being specified by a resonance time of the sustain discharge signal; And applying the discharge signal n times in succession, and applying the second sustain discharge signal specified m times in succession for a rise time due to resonance longer than the first sustain discharge signal.

In addition, a Y driver for driving the plurality of scan electrodes with respect to a plasma display panel including a plurality of scan electrodes, a plurality of sustain electrodes, and a plurality of address electrodes formed in a direction crossing the scan electrodes and the sustain electrodes. And an X driver for driving the plurality of sustain electrodes, an address driver for driving the plurality of address electrodes, and a controller for generating and transmitting a scan signal, a sustain discharge signal, and an address signal to each of the drivers, In a driving apparatus of a plasma display panel including a charge / discharge capacitor, an inductor serving as a power transmission path, and an energy recovery circuit including a plurality of switches, the control unit may be configured by resonance of a sustain discharge signal applied to the scan electrode or sustain electrode. Successively, n first sustain discharge signals having specified rise times Generating a second sustain discharge signal group in which adjacent m first sustain discharge signal groups and a second sustain discharge signal in which m specified second sustain discharge signals are successively longer than the first sustain discharge signal are longer than the first sustain discharge signal. do.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram showing a conventional driving device of the plasma display panel 1 to which the present invention is applied.

Referring to FIG. 3, the driving apparatus includes a plurality of scan electrodes, a plurality of sustain electrodes, and a plurality of address electrodes formed in a direction crossing the scan electrode and the sustain electrode. And a Y driver 36 for driving the plurality of sustain electrodes, an X driver 34 for driving the plurality of sustain electrodes, and an address driver 32 for driving the plurality of address electrodes. And a controller 30 generating and transmitting an address signal.

The controller 30 includes a display data controller 311 and a drive controller 312, the display data controller 311 includes a frame memory 301, and the drive controller 312 includes a scan controller 302. The common control unit 303 is included.

The Y driver 36 includes a scan driver 362 and a Y common driver 368.

The controller 30 receives a clock signal CLK, a data signal DATA, a vertical synchronization signal V _SYNC , and a horizontal synchronization signal H _SYNC from the outside. The display data controller 311 stores the data signal DATA in the internal frame memory 301 according to the clock signal CLK, and inputs a corresponding address control signal to the address driver 32.

The driving control unit 312 that processes the vertical synchronizing signal V _SYNC and the horizontal synchronizing signal H _SYNC includes a scanning control unit 302 and a common control unit 303. The scan controller 302 generates signals for controlling the scan driver 362, and the common controller 303 generates signals for controlling the Y common driver 368 and the X driver 34. The address driver 32 Processes the address control signal from the display data controller 311 and applies corresponding display data signals to the address electrode lines A1, ..., Am of the panel 1 in the address step. The scan driver 362 of the Y driver 36 applies a corresponding scan drive signal to each of the Y electrode lines Y1, ..., Yn in the address step in accordance with a control signal from the scan controller 302. The Y common driver 368 of the Y driver 36 simultaneously applies the common drive signal to the Y electrode lines Y1,..., Yn in the sustain discharge step in accordance with a control signal from the common controller 312. The X driver 34 simultaneously applies the common drive signal to the X electrode lines X1,..., Xn in the sustain discharge step in accordance with a control signal from the common controller 303.

FIG. 4 is an energy recovery circuit for applying a sustain discharge signal voltage Vs to a scan electrode or a sustain electrode of a driving circuit of a plasma display panel included in the Y driver 36 or the X driver 34. ). The energy recovery circuit shown in Fig. 4 is an L.F. Circuits proposed by Weber (US Pat. Nos. 4,866,349 and 5,081,400).

Referring to FIG. 4, a panel capacitor (Cp) in which each cell of the plasma panel is replaced with a capacitor, a voltage source (Vs, GND) of a sustain discharge signal, an inductor (L) generating an LC resonance and serving as a power transfer path, The capacitor (Cr) to charge and discharge, the diode (D1, D2) to prevent the reverse flow of current, the switch (S3, S4) for controlling the connection of the voltage source and the panel capacitor and the energy charge or supply of the capacitor (Cr) It includes a switch (S1, S2) for adjusting the (source).

When the switch S1 is turned on to apply the sustain discharge signal voltage Vs to the sustain electrode or the scan electrode, a resonance path is formed by the capacitor Cr, the inductor L, and the panel capacitor Cp to form the panel capacitor Cp. Voltage of the first terminal (which corresponds to the sustain electrode or the scan electrode) rises to near the Vs voltage.

The S3 switch is turned on while the first terminal of the panel capacitor Cp rises to near the Vs voltage, thereby clamping the voltage of the first terminal of the panel capacitor Cp to the Vs voltage. In this way, the sustain discharge signal voltage Vs is applied to the sustain electrode or the scan electrode.

On the other hand, when the switch S2 is turned on to lower the voltage applied to the panel capacitor, a resonance path is formed by the capacitor Cr, the inductor L, and the panel capacitor Cp to charge the panel capacitor Cp. The voltage is charged with the capacitor Cr.

Thereafter, the switch S4 is turned on to apply the GND voltage.

FIG. 5 is a diagram illustrating light output according to changing the rising slope of the sustain discharge signal by adjusting the switching timing of the energy recovery circuit of FIG. 4.

Referring to (a) and (b) of FIG. 5, it can be seen that the light output varies depending on the time taken to turn on the switch S3 after the switch S1 is turned on, that is, the length of the resonance time (rising time). have.

 That is, as shown in FIG. 5A, when the switch S3 is turned on at a relatively short resonance time t1 after the switch S1 is turned on, the sustain discharge signal rapidly rises to the voltage Vs within a short time. It is clamped to have a relatively strong light output, and as shown in (b) of FIG. 5, when the switch S1 is turned on at a relatively long resonance time t2 after the switch S1 is turned on, Vs due to resonance The portion rising to the voltage becomes relatively long, so that the light output is relatively weak. At this time, as can be seen in Figure 5 (a) and (b) it can be seen that the rising slope of the sustain discharge signal is different from each other. That is, in the above-described embodiment of the present invention, the method of changing the rising slope of the sustain discharge signal by adjusting the resonance time of the energy recovery circuit, that is, the turn-on times of the switches S1 and S3 as shown in FIGS. 4 and 5. It is possible.

As shown in (a) of FIG. 5, a signal having a short resonance time, that is, a signal having a relatively large rising slope of the sustain discharge signal has a relatively short time required for the sustain voltage to rise to Vs. It has the effect of strengthening the output, thereby eliminating the problem of the lower room. However, as the switching time is shortened, there is a problem that a greater burden is placed on the temperature of the switching element.

On the other hand, as shown in (b) of FIG. 5, a signal having a long resonance time, that is, a signal having a relatively small rising slope of the sustain discharge signal has a relatively long time taken for the sustain voltage to rise to Vs, so that the light output is relatively high. Although weak, it is effective in improving the high temperature problem in the panel.

As described above, when the sustain discharge signal having a short resonance time is referred to as the first sustain discharge signal, and the sustain discharge signal having a relatively long resonance time than the first sustain discharge signal is referred to as the second sustain discharge signal, it is effective in solving the problem of the lower part. The first sustain discharge signal and the second sustain discharge signal effective in solving the high temperature problem are mixed appropriately to reduce the high temperature bottom.

6 is a diagram illustrating a driving waveform to which the above-mentioned first and second sustain discharge signals are applied according to an embodiment of the present invention.

Referring to FIG. 6, two groups of sustain discharge signals having different rise times due to resonance are applied to the X / Y electrodes.

If the rise time due to resonance of the first sustain discharge signal is t1 and the rise time due to resonance of the second sustain discharge signal is t2, there is a relationship of t1 <t2. However, the time from an ascending time to just before descending is equal to T.

Preferably, the rise time due to the resonance of the first sustain discharge signal is specified by the time required to rise to half of the maximum amplitude Vs.

In this case, adjusting the rise time due to the resonance may include the first switch S1 for controlling the connection between the capacitor Cr for power charging and charging included in the power recovery circuit of FIG. 4 and the inductor L serving as a power transmission path. After being turned on, the timing is controlled by adjusting the turn-on timing of the second switch S3 for controlling the connection between the voltage source Vs for supplying the sustain voltage and the scan electrode. The turn-on timing adjusting unit is a driving control unit 312 included in the control unit 30 shown in FIG. 3, and the driving control unit 312 may switch timing (FIG. 4) to adjust the rise time of the sustain discharge signal. The control signal for the ON timing of the S3 switch of the &quot; &quot;

Preferably, the first sustain discharge signal is applied n times consecutively and then the second sustain discharge signal is applied m consecutively.

This is because by continuously applying the first sustain discharge signal, the light output is strengthened to solve the low discharge problem, and then the second sustain discharge signal is continuously applied to reduce the temperature rise due to the continuous application of the first sustain discharge signal. It is effective to let.

As described above, the first sustain discharge signal group in which n first sustain discharge signals are continuously adjacent to each other through the driving controller 312 and the second sustain discharge signal in which m second sustain discharge signals are continuously adjacent to each other. It can be implemented by applying a control signal for the switch timing to create a group.

  On the basis of the above-described contents, the experiment was conducted to determine whether the lower room was reduced by adjusting the mixing ratio of the first sustain discharge signal and the second sustain discharge signal.

FIG. 7 is a graph of experimental data on a lower reduction effect according to a mixing ratio of a first sustain discharge signal and a second sustain discharge signal.

Referring to FIG. 7, the X axis represents a mixing ratio of the first sustain discharge signal and the second sustain discharge signal, and the Y axis represents the number of pixels in which the lower side is generated.

One pixel is a unit in which all R, G, and B cells are gathered. The 42-inch panel used in this experiment includes a total of 768 lines, and each line includes 1024 pixels. 768 * 1024 = 786432 pixels.

Looking at the relationship between the blending ratio and the pixel where the lower side occurs, when a total of 128 pairs of sustain discharge signals are applied in one subfield, only one pair of first sustain discharge signals are applied and 127 pairs of second sustain discharge signals are applied. In this case, there were 21845 pixels in which the bottom was generated. However, when 30 pairs of the first sustain discharge signal were applied and 98 pairs of the second sustain discharge signal were applied, 624 pixels were generated in the bottom and the reduction effect of the bottom was remarkable. can see.

Therefore, the ratio of mixing the first sustain discharge signal among all sustain discharge signals applied in the single subfield constituting the screen of the plasma display panel is at least 1/3 or more.

In addition, although FIG. 6 illustrates a method of first applying a sustain discharge signal to the Y electrode, the sustain discharge signal may be applied to the X electrode first.

8 is a diagram illustrating a driving waveform to which the above-mentioned first and second sustain discharge signals are applied according to another embodiment of the present invention.

Referring to FIG. 8, the first and second sustain discharge signals may be applied to only one of the scan electrode and the sustain electrode to have the same effect as the embodiment of FIG. 6. To this end, the controller applies the first and second sustain discharge signals to only one of the scan electrode and the sustain electrode.

As in FIG. 6, the nth sustain discharge signal is applied m times consecutively after the first sustain discharge signal is applied n times in succession, and is applied to only one of the scan electrode and the sustain electrode.

In addition, the ratio of mixing the first sustain discharge signal among all sustain discharge signals applied in a single subfield constituting the screen of the plasma display panel is at least 1/3 or more.

On the other hand, in the resonant circuit for implementing the embodiment of FIG. 8, unlike in FIG. 4, the GND terminal may be substituted for the energy charging capacitor Cr, and at the bottom of the switch S4, -Vs is used instead of GND. Connect the voltage source.

As described above, it is possible to reduce the low temperature at a high temperature by changing a part of a control signal input to each scan driver or sustain driver through the control unit of the plasma display panel driver without large change in the existing circuit configuration.

As shown in the graph of FIG. 7 mentioned above, when 30 pairs are applied to the first sustain discharge signal, only one pair of the first sustain discharge signals is observed, and the reduction effect of the low temperature generated at a high temperature is clear. Thus, by mixing the first sustain discharge signal and the second sustain discharge signal, it is possible to confirm the effect of reducing the bottom generated at a high temperature.

Claims (14)

Energy comprising a plurality of scan electrodes, a plurality of sustain electrodes, a plurality of address electrodes formed in a direction crossing the scan electrode and the sustain electrode, and a capacitor for power charging and charging, an inductor serving as a power transmission path, and a plurality of switches In a driving method of a plasma display panel including a recovery circuit, Applying a first sustain discharge signal specified n times (n is a natural number) successively for a rise time caused by resonance of the sustain discharge signal applied to the scan electrode or the sustain electrode; And applying the second sustain discharge signal m consecutively (m is a natural number) after the step of applying the first sustain discharge signal n times in succession to a rise time due to resonance longer than the first sustain discharge signal. And a plasma display panel driving method. The method of driving a plasma display panel according to claim 1, wherein the rise time due to resonance of the first sustain discharge signal is specified as a time required to rise to a half point of the maximum amplitude Vs of the sustain discharge signal. . 2. The driving of the plasma display panel according to claim 1, wherein the ratio of the first sustain discharge signal to all of the sustain discharge signals applied within a single subfield constituting the screen of the plasma display panel is specified to be 1/3 or more. Way. The method of claim 1, wherein the rise time is controlled by adjusting a connection between a voltage source supplying a sustain voltage and a scan electrode after a first switch for controlling a connection between the capacitor for power charging and charging and an inductor serving as a power transmission path is turned on. And controlling the turn-on timing of the second switch. Energy comprising a plurality of scan electrodes, a plurality of sustain electrodes, a plurality of address electrodes formed in a direction crossing the scan electrode and the sustain electrode, and a capacitor for power charging and charging, an inductor serving as a power transmission path, and a plurality of switches In the driving method of the plasma display panel including a recovery circuit, wherein the sustain discharge signal is applied to only one of the scan electrode and the sustain electrode, Applying a first sustain discharge signal specified n times (n is a natural number) consecutively for a rise time due to resonance of the sustain discharge signal; And applying the second sustain discharge signal m consecutively (m is a natural number) after the step of applying the first sustain discharge signal n times in succession to a rise time due to resonance longer than the first sustain discharge signal. And a plasma display panel driving method. 6. The method of driving a plasma display panel according to claim 5, wherein the rise time due to resonance of the first sustain discharge signal is specified by a time required to rise to a half point of the maximum amplitude Vs. 6. The driving of the plasma display panel according to claim 5, wherein the ratio of the first sustain discharge signal to all of the sustain discharge signals applied within a single subfield constituting the screen of the plasma display panel is specified to be 1/3 or more. Way. The voltage source of claim 5, wherein the rise time includes a voltage source supplying a sustain voltage after turning on a first switch for controlling a connection between a power charging / discharging capacitor included in the power recovery circuit and an inductor serving as a power transmission path. And controlling the turn-on timing of the second switch for controlling the connection with the electrode. The voltage source and the scan electrode of claim 5, wherein the rise time includes a voltage source for supplying a sustain voltage after a first switch for controlling a connection between the ground terminal included in the power recovery circuit and an inductor serving as a power transmission path is turned on. And controlling the turn-on timing of the second switch to control the connection of the plasma display panel. A Y driver for driving the plurality of scan electrodes with respect to a plasma display panel including a plurality of scan electrodes, a plurality of sustain electrodes, and a plurality of address electrodes formed in a direction crossing the scan electrodes and the sustain electrodes; An X driver for driving a sustain electrode, an address driver for driving the plurality of address electrodes, and a controller for generating and transmitting scan signals, sustain discharge signals, and address signals to the Y driver, the X driver, and the address driver. In the driving apparatus of the plasma display panel including an energy recovery circuit including a capacitor for power charging and discharging, an inductor serving as a power transmission path, and a plurality of switches, The control unit includes: a first sustain discharge signal group in which n first sustain discharge signals (n is a natural number) consecutively adjacent to each other specify a rise time due to resonance of a sustain discharge signal applied to the scan electrode or the sustain electrode; A second sustain discharge signal group applied after the first sustain discharge signal group and continuously adjoining m second sustain discharge signals (m is a natural number) which has a rise time due to resonance longer than the first sustain discharge signal. And a driving apparatus for the plasma display panel. The driving apparatus of the plasma display panel according to claim 10, wherein the rise time due to the resonance of the first sustain discharge signal is specified as a time required to rise to a half point of the maximum amplitude Vs of the sustain discharge signal. . The plasma display panel as claimed in claim 10, wherein a ratio of the first sustain discharge signal group among all sustain discharge signals applied within a single subfield constituting the screen of the plasma display panel is specified to be 1/3 or more. Drive system. The method of claim 10, wherein the controller is configured to adjust a connection between the voltage source supplying a sustain voltage and the scan electrode from a turn-on time of the first switch that controls the connection between the capacitor for power charging and charging and the inductor serving as a power transmission path. 2. The driving apparatus of the plasma display panel of claim 2, wherein the rise time due to the resonance is controlled by adjusting a time interval until the turn-on time of the switch. The apparatus of claim 10, wherein the controller applies the first and second sustain discharge signal groups to only one of the scan electrode and the sustain electrode.

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